AI in Pharmacy Medication Adherence Programs

Adherence is usually measured from pharmacy claims, not by watching patients take pills. The most common metric is proportion of days covered (PDC): the share of days in a period on which the patient had medicine on hand, based on fill dates and days supplied. A PDC of 80 percent or more is the usual threshold for counting a patient as adherent. The Pharmacy Quality Alliance develops widely used adherence measures. Medicare Part D Star Ratings include adherence measures for non-insulin diabetes medicines, renin-angiotensin system antagonists and statins, and these have carried substantial weight in plan ratings. As a result, plans reward pharmacies that improve these numbers. Prediction models use signals such as prior fill history, whether a drug is newly started, copay, number of medicines, pharmacy changes, recent hospital stays and late first refills. Their job is to decide who gets limited pharmacist time. The interventions matter more than the prediction. Medication synchronization, sometimes called the appointment-based model, lines refills up to one date and adds a regular check-in. Other interventions include 90-day supplies, delivery, simpler regimens, help with cost and conversations about side effects or beliefs. Two misconceptions are common. First, a refill does not prove the patient took the medicine. PDC measures possession, and automatic refills can raise PDC without changing behavior. Second, the patients with the highest risk are not always the best ones to contact. Some would stop regardless, and others would refill without help. The goal is to reach patients whose behavior outreach can actually change.